Abstract

The early’ skill models’ of driver behaviour and safety posited that the safety of a driver is mainly determined by the level of his or her perceptual and motor skills in relation to the task demands: a crash — a failure in driver performance —occurs when task demands exceed driver capabilities (e.g., Blumenthal, 1968). Consequently, improving driver skills and reducing task demands would make traffic safer. Obviously, however, this early concept was too simple. A good piece of counterevidence, among others, came from (1974), who showed that classified U.S. race drivers have more crashes per exposure than average drivers — and also more speeding tickets. At least the advanced skills which make those drivers competitive in race track did not save them from crashes, as they obviously traded skills for speed on ordinary roads, too. Theorists and road safety people indeed forgot that driving is a self-paced task and drivers themselves do determine their task demands to a large extent (Näätänen and Summala, 1974). The behavioural adaptation concept is now one of basic tenets in traffic psychology, here defined by (1996): ‘the driver is inclined to react to changes in the traffic system, whether they be in the vehicle, in the road environment, in road and weather conditions, or in his/her own skills or states, and that this reaction occurs in accordance with his/her motives’.

This is an extension of the author’s earlier paper presented in the symposium on traffic psychology theories in the 3rd International Congress of Traffic and Transport Psychology (see Summala, 2005).

Wikman, A.-S., Laakso, M. and Summala, H. (1997). Time sharing of car drivers as a function of driving speed and task eccentricity. In The 13th Triennial Congress of International Ergonomics Association. Tampere, Finland, June 29–July 4, 1997.